BRUSSELS—Europe’s latest plan to protect migrants in the Mediterranean will likely save lives, but it will also block many more people seeking asylum from reaching Europe, refugee advocates and experts say.

That reality reflects the region’s mixed feelings about serving as the world’s destination of choice for people fleeing war, poverty and oppression. The deaths of over 800 migrants this week after their boat capsized have forced politicians to balance powerful competing concerns: the humanitarian desire to save lives,...

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The Deadliest Migrant Route in the World

The boat journey across the Mediterranean from Libya to the Italian island of Lampedusa has claimed over 1,000 lives in 2015 alone. Why is it so perilous? (NOTE: An earlier version of this video incorrectly identified the location of Lampedusa.)